public class StockCommonFunctions
{
    public static bool CheckIfZhuBan(string stockCode)
    {
        return stockCode.StartsWith("000") || stockCode.StartsWith("001") || stockCode.StartsWith("002") || stockCode.StartsWith("003")
               || stockCode.StartsWith("600")|| stockCode.StartsWith("601")|| stockCode.StartsWith("603")|| stockCode.StartsWith("605");
    }
}